Among rotors for a rotary electric machine, there is given a rotor including a non-magnetic ring configured to retain permanent magnets mounted on a periphery of the rotor.
For example, in Patent Literature 1, there is disclosed a rotor including at least a rotor core, a plurality of magnets, and a non-magnetic ring. The plurality of magnets are fixed to an outer periphery of the rotor core so as to be arrayed in a circumferential direction. The non-magnetic ring is provided so as to surround the plurality of magnets from outside.
Further, in Patent Literature 2, there is disclosed a step-skew configuration, in which upper and lower stages of a rotor are shifted by a predetermined angle in a circumferential direction so as to reduce cogging torque and torque ripples.